user
Write a response that appropriately completes the request.

### Instruction:
How would you explain what a blockchain is to a non-technical person?

### Response:
assistant
A blockchain is a decentralized digital ledger of transactions shared across a network of computers. It operates without a central authority, which means that no single user or entity can alter or remove records. The technology stores data in securely encrypted blocks which are linked together in a chronological chain. Transactions added to the blockchain are validated by a consensus process and once validated, can never be altered or removed. This makes the blockchain incredibly secure and efficient for recording and validating transactions.